TWI516871B - Negative-type photoresist composition for thick film and use thereof - Google Patents

Description

Negative thick film photoresist composition and use thereof

The present invention relates to a negative thick film photoresist composition and use thereof, and more particularly to a negative type thick film photoresist composition suitable for an electroplating process and use thereof.

In recent years, with the development of miniaturized electronic devices, the industry has also pursued the development of high-density packaging technologies such as multi-lead film encapsulation and miniaturization of package size.

Thick film photoresist is an important key material for the above semiconductor packaging process, and can be used, for example, in a bump process in which bumping or metal posts are formed by electroplating. However, since the plating solution conventionally used for making bumps or metal posts usually contains cyanide or non-cyanide, such thick film photoresist is often difficult to maintain its shape during the process, and is easy. Deformation or thick film photoresist peeling, causing problems such as line conduction and short circuit. Furthermore, in the electroplating process of the wafer, it is also necessary to consider the adhesion between the thick film photoresist and the substrate, for example, whether the thick film photoresist is easily stripped from the substrate before and after the electroplating process, in the electroplating process. Whether the thick film photoresist maintains good adhesion to the substrate.

Therefore, develop a thick film that can be used for the bump process of germanium wafers. The photoresist has high sensitivity, good adhesion to the ruthenium wafer substrate, and poor deformation of the plating. It is helpful for promoting the development of related industries.

The main object of the present invention is to provide a negative thick film resist composition which can be prepared by the alkali-soluble resin having a rigid structure and the bisphenol hydrazine derivative monomer contained in the composition. A negative-type thick film photoresist composition that maintains good adhesion to the wafer substrate and is not easily deformed by plating, so as to be applied to the bump process of the germanium wafer.

In order to achieve the above object, an aspect of the present invention provides a negative thick film resist composition comprising: (A) 20 to 50% by weight of an alkali-soluble resin, which can be polymerized from a plurality of monomers, wherein The monomers may include a compound represented by the formula (1A) and the formula (1B), and based on the weight ratio of the monomers to the alkali-soluble resin, the compound of the formula (1A) and the compound of the formula (1B) A total of 20 to 60%, and X in the formula (1A) and the formula (1B) may each independently be hydrogen, methyl or ethyl. (B) 10 to 30% by weight of a crosslinking agent which may be a bisphenolphthalein derivative monomer having at least one ethylenically unsaturated double bond; (C) 5 to 15% by weight of a photoinitiator; (D) The balance of solvent.

In the negative thick film resist composition of the present invention, in order to adjust the compatibility of the alkali-soluble resin of the component (A) with other components, the monomer for polymerizing the alkali-soluble resin of the present invention may further comprise Other types of monomers. For example, in one aspect of the invention, the monomers may further comprise a compound of formula (1C), a compound of formula (1D), or a combination thereof.

In the above negative-type thick film photoresist composition of the present invention, the alkali-soluble resin is preferably polymerized from a plurality of monomers, and the monomers may be of the formula (1A), the formula (1B), and the formula (1). 1C), and a compound of the formula (1D), wherein the compound of the formula (1A) and the compound of the formula (1B) together account for 20 to 60%, based on the total weight ratio of the monomers to the alkali-soluble resin, the formula (1C) The compound is 10 to 30%, the compound of the formula (1D) is 10 to 20%, and the X of the formula (1A) and the formula (1B) may each independently be hydrogen, methyl or ethyl.

In the above negative-type thick film photoresist composition of the present invention, in addition to the compatibility between the alkali-soluble resin and other components, it is also possible to The conditions such as the weight average molecular weight, the degree of polymerization, or the acid value of the alkali-soluble resin are controlled within an appropriate range to facilitate application of the negative-type thick film resist composition. For example, in one aspect of the invention, the alkali soluble resin may have a polydispersity index (PDI) of from 1 to 3 and a weight average molecular weight of from 8,000 to 30,000 g/mole. When the weight average molecular weight of the alkali-soluble resin is less than 8,000 g/mole, the alkali-soluble resin may have poor chemical resistance, so that the negative-type thick film resist composition containing the same cannot be applied to the applied process. Maintain sufficient stability to cause the photoresist to dissolve or deform. When the weight average molecular weight of the alkali-soluble resin is higher than 30,000 g/mole, the resolution of the photoresist formed by the negative-type thick film resist composition may not reach the standard required for the process. Therefore, in the preparation of the negative-type thick film resist composition of the present invention, in addition to considering the compatibility between the alkali-soluble resin and other constituent components, it is also possible to utilize the present invention by controlling the molecular weight range thereof. The photoresist prepared by the negative thick film resist composition can have excellent chemical resistance and appropriate resolution.

In the negative thick film resist composition of the present invention, as long as it can be used in a negative thick film resist composition and has at least one ethylenically unsaturated double bond to provide photopolymerization, various types The bisphenol hydrazine derivative monomer can be used as the component (B) of the above-mentioned negative thick film resist composition of the present invention, and the present invention is not particularly limited thereto. For example, in one aspect of the invention, the bisphenolphthalein derivative monomer may be a compound represented by the following formula (2). Wherein m, n, x, and y may each independently be a positive integer of 0 to 2, and at least one of m, n, x, and y may not be zero. Further, in another aspect of the present invention, in the compound of the formula (2), m+n+x+y may be greater than or equal to 2, so that the crosslinking reaction can be more efficiently achieved. More specifically, in one embodiment of the present invention, the bisphenolphthalein derivative monomer may be an ethoxylated bisphenolphthalein diacrylate represented by the following formula (2A).

Furthermore, in the above negative-type thick film photoresist composition of the present invention, those skilled in the art can also add various types of additives according to the desired characteristics of the prepared negative-type thick film photoresist composition, and the present invention does not In particular, this is limited. In addition, as long as the prepared negative-type thick film photoresist composition can be achieved The characteristics required, and still retain the characteristics of the above-mentioned negative-type thick film resist composition of the present invention, such as good adhesion and electroplating are not easily deformed, and the content range of the additive is not particularly limited in the present invention. For example, in one aspect of the invention, the negative thick film photoresist composition may further comprise greater than 0 to 10 weight percent inhibitor. In another aspect of the invention, the negative photoresist composition may further comprise greater than 0 to 10 weight percent of an adhesion promoter. In still another aspect of the invention, the negative photoresist composition may further comprise greater than 0 to 10 weight percent of a leveling agent.

In the above negative-type thick film photoresist composition of the present invention, any photoinitiator which can be used for a negative-type thick film photoresist composition can be used as a constituent of the present invention as far as photopolymerization can be initiated. C), the invention is not particularly limited thereto. For example, the photoinitiator can be, but is not limited to, aromatic ketones, p-aminophenyl ketones, benzoquinones, benzoin ether compounds, benzoin compounds, benzyl derivatives, phosphine oxides, hydrazines Phosphine oxide and the like. These photoinitiators may be used alone or in combination of two or more, and the present invention is not limited thereto. In addition, the photoinitiator may also be selected from any of the conventional commercially available products or combinations thereof, such as Irgacure ^® 184, Irgacure ^® 369, Irgacure ^® 500, Irgacure ^® 651, Irgacure ^® 784, Irgacure ^® 819 manufactured by Basf. Irgacure ^® 907, Irgacure ^® 1300, Irgacure ^® 2010, Irgacure ^® 2020, Irgacure ^® 2959, Darocur ^® 1173, or Darocur ^® 4265, or Chemcure-TPO manufactured by Hengqiao, but the invention is not limited thereto.

In the negative thick film resist composition of the present invention, any solvent which can be used for the negative thick film resist composition can be used as a component of the present invention as long as the other components can be appropriately dispersed. , the invention Not limited to this. For example, the solvent can be, but is not limited to, hexane, heptane, octane, decane, benzene, toluene, xylene, benzyl alcohol, methyl ethyl ketone, acetone, butanol, ethylene glycol. , diethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, 2-methoxybutyl acetate, 2-ethoxybutyl acetate, 4-methoxypentyl Acid ester, methyl lactate, butyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl acetate, methyl propionate, methyl benzoate, N, N-dimethyl Formamide, N-methyl-pyrrolidone, tetramethylguanidine, chloroform, or dichloromethane. These solvents may be used alone or in combination of two or more kinds, and the present invention is not limited thereto.

Accordingly, according to the negative photoresist composition formulation of the present invention, a negative thick film light having high sensitivity, good adhesion to the germanium wafer substrate, and non-deformation of plating can be prepared. Blocking composition.

Another object of the present invention is to provide a negative thick film resist composition comprising the alkali-soluble resin and the bisphenol hydrazine derivative having a rigid structure contained in the negative thick film resist composition of the present invention. The monomer is prepared to have a high sensitivity, a good adhesion to the ruthenium wafer substrate, and a plating resistance that is not easily deformed, thereby preventing problems such as deformation, deformation, dissolution, and falling off during the manufacturing process.

In order to achieve the above object, another aspect of the present invention provides a use of a negative thick film resist composition which can be used in an electroplating process of the above-described negative photoresist composition of the present invention.

More specifically, in the above-described use of the negative-type thick film photoresist composition of the present invention, the negative-type photoresist composition of the present invention can be applied to the surface of a substrate such as a wafer surface and transmitted through Appropriate exposure development process Form a photoresist layer. Then, the substrate on which the photoresist layer is formed may be subjected to an electroplating process to form a metal layer, such as a wiring layer or a bump, where the photoresist layer is not formed on the surface of the substrate. Finally, the photoresist layer on the surface of the substrate is stripped by appropriate treatment.

Since the negative photoresist composition of the present invention contains the composition as described above, the photoresist formed by the negative photoresist composition of the present invention does not peel off, deform, or In the case of dissolution, defects such as short circuits can be avoided, and the yield of the product can be improved. Therefore, the negative thick film resist composition of the present invention is quite suitable for use in any conventional plating process that requires photoresist, such as a bump process of a wafer package.

1A to 1C are diagrams showing the results of scanning electron microscopy of Example 1 of the present invention.

Examples 1 to 9

Referring to Table 1, the alkali soluble resin, the crosslinking agent, the photoinitiator, the inhibitor, the adhesion promoter, the leveling agent and the solvent are formulated according to the composition formulas shown in Tables 1 and 2 as Example 1 to A negative-type thick film resist composition of 9, wherein the alkali-soluble resin used is MB211 (benzyl acrylate/trimethacrylate) [5.2.1.0 ^2,6 ]癸-8-yl ester/methacrylic acid /glycidyl methacrylate; BzMA/TCDMA/MAA/MAA-GMA, Mw≒13000, PDI≒2.55, acid number (AN)≒98mgKOH/g, manufactured by Miwon), MB120 (benzyl acrylate/A) Tricyclohexyl acrylate [5.2.1.0 ^2,6 ] 癸-8-yl ester / methacrylic acid / glycidyl methacrylate; BzMA / TCDMA / MAA / MAA-GMA, Mw ≒ 10000, acid number (acid number, AN) ≒130 mgKOH/g, manufactured by Miwon), BL100 (benzyl acrylate/methacrylic acid/hydroxyethyl methacrylate; BzMA/MAA/HEMA, Mw≒10000, acid number (AN) ≒100 mgKOH/g , manufactured by Lida), cross-linking agent is ethoxylated bisphenol fluorene diacrylate (Bestred bisphenol fluorene diacrylate, BPF-022 and BPF-102, manufactured by HANNONG Chemicals), light start As Irgacure ^® 819, Irgacure ^® 369 and Chemcure-TPO (manufactured permanent bridge), inhibitor is hydroquinone (Hydroquinone), adhesion promoting agent Z-6011 (DOW CORNING, Ltd.), a leveling agent is R-41 ( The solvent produced by DIC) and the solvent were propylene glycol monomethyl ether acetate (CAS No. 108-65-6), and the contents of the components of the respective examples are shown in Tables 1 and 2.

Comparative example 1

Comparative Example 1 is substantially similar to Example 1 above except that a copolymer of methacrylic acid/methyl methacrylate/isooctyl acrylate (MAA/MMA/2-EHA, 8450-S-40, Mw ≒ 30000, Replaced the alkali-soluble resin of Example 1 and substituted BPF-022 as a crosslinking agent with pentaerythritol tetraacrylate (EM241, Mw≒352, manufactured by Changxing), other components and contents, and examples the same.

Comparative example 2

Comparative Example 2 is substantially similar to the above-described Embodiment 1, except that The base acrylic acid/methyl methacrylate/isooctyl acrylate copolymer (MAA/MMA/2-EHA, 8450-S-40, Mw≒30000, manufactured by Changrun) is substituted for the alkali-soluble resin of Example 1. BPF-022 was replaced by tricyclodecane dimethanol diacrylate (EM2204, manufactured by Changxing) as a crosslinking agent, and other components and contents were the same as in the examples.

Comparative example 3

Comparative Example 3 is substantially similar to the above Example 1, except that a copolymer of methacrylic acid/methyl methacrylate/isooctyl acrylate (MAA/MMA/2-EHA, 8450-S-40, manufactured by Changrun) The base-soluble resin of Example 1 was replaced, and BPF-022 was replaced with DM87A (manufactured by double bond chemistry) as a crosslinking agent, and other components and contents were the same as in the examples.

Comparative example 4

Comparative Example 4 is substantially similar to the above Example 3 except that a copolymer of methacrylic acid/methyl methacrylate/isooctyl acrylate (MAA/MMA/2-EHA, 8450-S-40, manufactured by Changrun) The alkali-soluble resin of Example 3 was replaced, and the other components and contents were the same as in the examples.

Comparative Example 5

Comparative Example 5 is substantially similar to Example 3 above except that a copolymer of methacrylic acid/methyl methacrylate/isooctyl acrylate/glycidyl methacrylate (MAA/MMA/2-EHA/MAA-GMA) , 8546-S-40, Mw≒16000, manufactured by Changrun), replacing the alkali-soluble resin of Example 3, and pentaerythritol tetraacrylate (EM241, Mw≒352, manufactured by Changxing) Instead of BPF-102 as a crosslinking agent, other components and contents are the same as in the examples.

矽 Wafer plating process test

Preparation of Samples

First, a substrate is provided which is a tantalum wafer having a 1000 Å gold layer on its surface. A negative-type thick film resist composition prepared in the above Examples 1 to 9 and Comparative Examples 1 to 5 having a thickness of 20 μm was applied to the surface of the substrate, and baked at 110 ° C for 5 minutes. Next, the negative thick film resist composition was exposed with SEIWA-500UV and developed with 2.38% tetramethylammonium hydroxide (TMAH) at 23 ° C to form a photoresist layer. Finally, it was washed with secondary water at 25 ° C for 30 seconds. The photoresist layer on the surface of each sample substrate was observed by a scanning electron microscope to evaluate the resolution and residual degree of the photoresist layer formed by the negative-type thick film resist compositions of Examples 1 to 9 and Comparative Examples 1 to 5. .

Electroplating Process

The samples prepared by using the negative-type thick film resist compositions of Examples 1 to 9 and Comparative Examples 1 to 5 described above were respectively immersed in a cyanide type gold plating solution (manufactured by JPC) at a current density of 0.4. (A/dm ² , Ampere per Square Decimeter (ASD)), electroplated at 60 ° C for 30 minutes to form a metal layer at the surface of each of the sample substrate surfaces where the photoresist layer was not formed. In this test example, the metal layer was a bump. Finally, it was washed with secondary water at 25 ° C for 30 seconds. After the electroplating treatment, the photoresist layer on the surface of each sample substrate was observed by a scanning electron microscope to evaluate the photoresist layer formed by the negative-type thick film resist compositions of Examples 1 to 9 and Comparative Examples 1 to 5. Resistance to electroplating.

Finally, each of the above samples was immersed in N-methyl-2-pyrrolidone (NMP) at 60 ° C for 20 minutes to strip the photoresist layer on the surface of each sample substrate. Next, it was washed with secondary water at 25 ° C for 30 seconds. The residual state of the photoresist layer on the surface of the substrate was observed by a scanning electron microscope to evaluate the peeling state of the photoresist.

"evaluation result"

Please refer to Table 3 and refer to Table 4, wherein Table 3 is the evaluation standard of each evaluation item, and Table 4 is the preparation of the negative type thick film photoresist composition of the above Examples 1 to 9 and Comparative Examples 1 to 5. The evaluation results of the samples. The evaluation order is sequentially the resolution of the photoresist layer, the residue when the photoresist layer is formed, the chemical strength of the photoresist layer, and the stripping of the photoresist layer. . As shown in Table 4, the negative-type thick film photoresist compositions prepared in Examples 1 to 9 were able to pass all evaluations. In other words, as shown in FIGS. 1A to 1C, the negative-type thick film resist composition prepared by the present invention can be formed to have good resolution (FIG. 1A), and in the electroplating process, the formed photoresist layer does not peel off (FIG. 1A). Figure 1B), after the electroplating process, the photoresist layer can be completely stripped without any residue on the substrate (Fig. 1C).

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

(The figure is a result diagram, so there is no component symbol)

Claims (9)

A negative thick film photoresist composition for use in an electroplating process, the negative photoresist composition comprising: (A) 20 to 50 weight percent of an alkali soluble resin polymerized by a plurality of monomers The compound of the formula (1A) and the compound of the formula (1B) based on the weight ratio of the monomer to the alkali-soluble resin, and the compound of the formula (1B) The two are a total of 20 to 60%, and the X series of the formula (1A) and the formula (1B) are each independently hydrogen, methyl or ethyl. (B) 10 to 30% by weight of a crosslinking agent which is a bisphenolphthalein derivative monomer having at least one ethylenically unsaturated double bond; (C) 5 to 15% by weight of a photoinitiator; (D) The balance of solvent. The negative-type thick film photoresist composition according to claim 1, wherein the monomers further comprise a compound of the formula (1C), a compound of the formula (1D), or a combination thereof. The negative-type thick film resist composition according to claim 1, wherein the alkali-soluble resin has a weight average molecular weight of 8,000 to 30,000 g/mole, and a polymerization degree distribution index of 1 is 1 To 3. The negative-type thick film resist composition according to claim 2, wherein the alkali-soluble resin is obtained by polymerizing a plurality of monomers, and the single systems are as in the formula (1A), 1B), a compound of the formula (1C), and the formula (1D), wherein the compound of the formula (1A) and the compound of the formula (1B) together account for 20 to 60 based on the total weight ratio of the monomers to the alkali-soluble resin. %, the compound of the formula (1C) accounts for 10 to 30%, the compound of the formula (1D) accounts for 10 to 20%, and the X groups of the formula (1A) and the formula (1B) are each independently hydrogen, methyl or ethyl. The negative-type thick film resist composition according to claim 1, wherein the bisphenolphthalein derivative single system is a compound represented by the following formula (2), Wherein, m, n, x, and y are each independently a positive integer of 0 to 2, and at least one of m, n, x, and y is not zero. The negative-type thick film photoresist composition according to claim 5, wherein m+n+x+y is greater than or equal to 2. The negative-type thick film photoresist composition according to claim 1, wherein the negative-type photoresist composition further comprises more than 0 to 10% by weight of an inhibitor. The negative-type thick film photoresist composition according to claim 1, wherein the negative-type photoresist composition further comprises more than 0 to 10% by weight of an adhesion promoter. The negative-type thick film photoresist composition according to claim 1, wherein the negative-type photoresist composition further comprises more than 0 to 10% by weight of a leveling agent.